Hormones significantly influence weight gain and loss, primarily through their role in regulating metabolism, appetite, and fat storage. Hormones such as insulin, cortisol, and leptin work in tandem to control energy balance. For example, excess insulin can lead to fat storage, while cortisol, often triggered by stress, is associated with increased appetite and cravings. Balancing hormone levels through diet, exercise, and adequate sleep can facilitate healthy weight management and overall well-being.